This invention relates to a device for indicating the times of high or low tides at specific location along a stretch of coastline.
Tide Tables such as those issued annually by the U.S. Department of Commerce give complete listings for high and low tide times for each day of the year for major locations in a particular coastal area. For other locations however, no complete listings are given in the Tide Tables, although the Tables do give the general relationship in terms of time between certain such locations and one of the major locations for which a complete listing is given. Accordingly, to determine the time of a tide in one of the fully listed locations, it is necessary to consult the relevant listing; or to compute the time of a high or low tide at one of the other locations, it is necessary to consult the Tables to determine the tidal time difference between the required location and a fully listed location, then to consult the table for the day in question for the fully listed location and make the required addition or subtraction of time necessary for the location under review.
Knowledge of tide time is necessary for certain individuals such as fishermen and yachtsmen and it would be advantageous to such people to have available an expedient whereby the tide times at specific locations could be readily determined without the necessity for consulting the Tide Tables for a listed location and in the case of a non-listed location, making the necessary arithmetic calculations.
Accordingly, it is an object of the instant invention to provide a device for indicating tide times at specific locations which obviates the necessity to consult Tide Tables.
It is a further object of the invention to provide a tide time indicator which can be used to readily determine either high or low tide, A.M. or P.M. at any one of a number of specific locations for any day of a calendar year, such locations having a known tidal time relationship to a location having its tide times fully listed in the Tide Tables.
Another object of the invention is to provide a device of the above character which is simple to use and which is readily transportable.
A further object of the invention is to provide a device of the above character which is attractive to the eye and which can be constructed in the form of a novelty or souvenir to be sold in tourist or like stores at any one of the locations for which the device is intended to function.
A still further object of the invention is to provide a tidal time indicator which is more accurate than previously known tidal calculators. Such previously known devices (see, for example, Dutch Patent Specification No. 7609072 and U.S. Pat. Nos. 3,982,104 3,825,181 and 3,745,313) have been based on the principle of utilizing the mean difference between daily lunar and solar cycles and are accurate in the mean but ahead of the actual tide time for some calculations and behind the actual tide time for other calculations.
Yet another object of the invention is to provide a device for determining tide times at specific locations which device is economical and relatively simple to manufacture from readily available materials.